Rotatable sleeve for self-sharpening bit

ABSTRACT

A bit and block assembly in which a sleeve is rotatively mounted in a block bore and in which a point-attack bit has its elongate shank mounted in a sleeve bore and has a cutting tip on the leading end of the bit head that penetrates the material being mined with a picking action upon travel of the bit into and out of a mine face. A plurality of protuberances are provided on and extend outwardly from the periphery of the sleeve head, the protuberances providing frictional contact with the material being mined to effect positive turning of the sleeve, and hence of the bit in the sleeve, upon picking of the mine face by the bit head. In one embodiment, the protuberances consist of fins on and extending substantially lengthwise of the sleeve head and projecting laterally outwardly from the periphery of the sleeve head. In another embodiment, the protuberances consist of individual knobs formed on and projecting laterally outwardly from the periphery of the sleeve head. The protuberances are circumferentially spaced about the periphery of the sleeve head to provide longitudinal passages therebetween extending from its leading end to its trailing end, the material being mined being movable through the passages and engageable with the protuberances to effect positive turning of the sleeve and bit and to effect removal of the material being mined from the sleeve head. The sleeve head with its protuberances extends laterally outwardly beyond the outer block face to enable discharge of the material being mined from the passages between the circumferentially spaced protuberances.

United States Patent [191 Elders Sept. 3, 1974 ROTATABLE SLEEVE FORSELF-SHARPENING BIT [76] Inventor: Gerald W. Elders, 10 l-lillcrest St.,

Christopher, Ill. 62822 [22] Filed: Nov. 6, 1972 [21] Appl. No.: 304,242

Related US. Application Data [63] Continuation-impart of Ser. No.69,161, Sept. 2, 1970, abandoned, Continuation-in-part of Ser. No.498,638, Oct. 20, 1965, abandoned.

Elders 299/86 Primary ExaminerErnest R. Purser [57] ABSTRACT A bit andblock assembly in which a sleeve is rotatively mounted in a block boreand in which a pointattack bit has its elongate shank mounted in asleeve bore and has a cutting-tip on the leading end of the bit headthat penetrates the material being mined with a picking action upontravel of the bit into and out of a mine face. A plurality ofprotuberances are provided on and extend outwardly from the periphery ofthe sleeve head, the protuberances providing frictional contact with thematerial being mined to effect positive turning of the sleeve, and henceof the bit in the sleeve, upon picking of the mine face by the bit head.In one embodiment, the protuberances consist of fins on andextending'substantially lengthwise of the sleeve head and projectinglaterally outwardly from the periphery of the sleeve head. In anotherembodiment, the protuberances consist of individual knobs formed on andprojecting laterally outwardly from the periphery of the sleeve head.The protuberances are circumferentially spaced about the periphery ofthe sleeve head to provide longitudinal passages therebetween extendingfrom its leading end to its trailing end, the material being mined beingmovable through the passages and engageable with the protuberances toeffect positive turning of the sleeve and bit and to effect removal ofthe material being mined from the sleeve head. The sleeve head with itsprotuberances extends laterally outwardly beyond the outer block face toenable discharge of the material being mined from the passages betweenthe circumferentially spaced protuberances.

5 Claims, 4 Drawing Figures ROTATABLE SLEEVE FOR SELF-SI-IARPENING BITCROSS REFERENCE TO RELATED APPLICATIONS This application is acontinuation-in-part of copending U.S. Pat. application Ser. No. 69,161,filed Sept. 2, 1970 now abandonedwhich was a copending continuation ofU.S. Pat. application Ser. No. 498,638 filed Oct. 20, 1965 nowabandoned.

BACKGROUND OF THE INVENTION This invention relates generally toimprovements in a bit mounting, and more particularly to a mounting thatcauses the bit to turn automatically during cutting action to provide aself-sharpening of the bit head that results in longer bit wear andlife.

A self-sharpening bit has been realized by providing protuberances onthe conical head of the bit so that the protuberances will engage thematerial being mined during the picking action of the bit, thefrictional contact of the protuberances with the material causing thebit to rotate in its mounting in the block bore.

SUMMARY OF THE INVENTION The present bit and block assembly consists of-a sleeve rotatively mounted in a block bore, and a pointattack bithaving its elongate shank mounted in the sleeve bore and having acutting tip on the leading end of the bit head-that penetrates materialbeing mined with a picking action upon travel of the bit into and out ofa mine face. A plurality of protuberances are provided on and extendoutwardly from the periphery of the sleeve head, the protuberancesproviding frictional contact with the material being mined to effectpositive turning of the sleeve, and hence of the bit in the sleeve, uponpicking of the mine face by the bit head.

The provision of protuberances on the sleeve head realizes effectiverotation of the bit without sole reliance on any protuberances on thebit head as previously provided.

The protuberances are provided about the periphery of the sleeve headwith at least one protuberance in position to frictionally engage thematerial being mined to effect positive turning. Preferably, theprotuberances are circumferentially spaced relatively about the sleevehead periphery.

In one embodiment, the protuberances consist of fins on and extendingsubstantially lengthwise of the sleeve head and projecting laterallyoutwardly from the periphery of the sleeve head.

In another embodiment, the protuberances consist of individual knobsformed on and projecting laterally outwardly from the periphery of thesleeve head.

The sleeve head with its protuberances, engages the block front face toposition the sleeve in the block, and the bit head engages the sleevehead to position the bit in the sleeve. Upon cutting action, the forceof the bit head striking the mine face, urges the bit head rearwardlyagainst the sleeve head, and hence urges the sleeve head rearwardlyagainst the block front face. Accordingly, the bit and sleeve arefrictionally interconnected so that as the material being mined engagesand passes longitudinally between the protuberances on the sleeve headto effect a positive angular rotation of the sleeve, the sleeve will inturn angularly rotate the bit.

The protuberances are circumferentially spaced about the periphery ofthe sleeve head to provide longitudinal passages therebetween extendingfrom its leading end of the sleeve head to its trailing end, thematerial being mined being movable through the passages and engageablewith the protuberances to effect positive turning of the sleeve and bitand to effect removal of the material being mined from the sleeve head.

The block has an outer face adjacent to the front face. The sleeve headwith its protuberances engages the block front face to position thesleeve in the block and extends laterally outwardly beyond the outerblock face to enable discharge of the material being mined rearwardlyfrom the passages between the circumferentially spaced protuberances.

DETAILED DESCRIPTION OF THE DRAWING DESCRIPTION OF THE PREFERREDEMBODIMENTS Referring now by characters of reference to the drawing, andfirst to the embodiment of FIGS. 1-3, it will be understood that theblock 10 is provided with a substantially cylindrical bore 11 extendingthrough the front block face 12 and the rear block face 13. The bore 11is flared at the front block face 12 to provide an outwardly divergentshoulder 14. The block 10 includes an outer block face 15.

A point-attack bit generally indicated at 16 includes an elongate shank17 having a circular cross-section. A tapered head 20 is formedintegrally and coaxially with the shank 17, the head 20 tapering towardthe forward end of the bit to provide a reduced leading end 21 and arelatively enlarged trailing end 22. The bit shank 16 includes anenlarged, outwardly diverging shank portion 23 integrally connected tothe trailing end 22 of the bit head 20.

Inserted in and attached to the leading end 21 of the bit head 20 is acarbide cutting tip 24. The tip 24 is provided with a relatively sharppoint. The tapered bit head 20 including the carbide tip 24 picks at themine wall in order to cut away a portion of such wall. The tapered bitend 20' enters the wall with its leading end foremost and with itslongitudinal axis arranged at a slight angle to the surface of the wall,in an intermittent picking action.

Associated with both the block 10 and the bit 16 is a sleeve generallyindicated by 25. This sleeve includes an elongate shank 26 rotativelymounted in the block bore 1 l, the rearmost end 27 of the sleeve 25extending outwardly beyond the rear block face 13. The forwardmost endof the sleeve 25 includes an enlarged head 30 that can be tapered toprovide a reduced leading end 31 and an enlarged trailing end 32. Thesleeve shank 26 includes an enlarged, outwardly diverging shank portion33 integrally connected to the head 30, the shank portion 33 engagingthe annular bore shoulder 14.

The sleeve 25 includes a longitudinal bore 34 that is adapted to receivethe bit shank 16. The sleeve bore 34 is flared at the outermost face ofthe sleeve head 30 to provide an outwardly divergent shoulder 35. Whenthe bit 16 is assembled to the sleeve 25, the bit shank portion 23engages the annular sleeve shoulder 35'.

To look the sleeve 25 in the block 10, a pin 36 is inserted into theside of the block and into an annular groove 37 provided inthe sleeveshank 26. The rear block face 13 is immediately adjacent the lockingconnection provided by pin 36 and groove 37 to permit any foreignmaterial moving axially along the block bore 11 between the block 10 andsleeve shank 26 to fall freely out of the block for discharge, andthereby enable the sleeve shank 26 to rotate at all times in the blockbore 11.

When assembled, the bit shank 17 is selectively locked to the sleeveshank 26. A pin 40 is inserted'into the sleeve shank 26 and into acompatible annular groove 41 formed in the end of the bit shank 17. Therear end of the sleeve shank 26 is countersunk to provide a recessimmediately rearwardly of the annular groove 41 to permit any foreignmaterial moving axially along the sleeve bore 34 between the bit shank17 and sleeve shank 26 to fall freely out of the bore 34 for discharge.

To assemble this device, the bit shank 17 is usually first inserted intothe sleeve bore 34 until the bit shank portion 23 engages the sleeveshoulder 35. Then, the bit shank 17 is locked to the sleeve 25 byinserting the pin 40 into the sleeve shank 26 and into the annulargroove 41 of the bit shank 17. Then, the sleeve shank 26, together withits assembled bit 16, is inserted into the block bore 11 until thesleeve shank portion 33 engages the block shoulder 14. Then, a pin 36 isinserted into the block 10 and into the annular groove 37 of the sleeveshank 26 to lock the sleeve 25 in the block 10.

A plurality of protuberances42 are provided on and extend outwardly fromthe periphery of the sleeve head 30, the protuberances beingcircumferentially spaced so that at least one of theprotuberances willfrictionally engage the material being mined. Specifically, theprotuberances are spaced to provide longitudinal passages therebetweenextending from the leading end 31 to the trailing end 32 of the sleevehead 30. The material being mined is movable through the passages andengageable with the probuterances 42 to effect positive turning of thesleeve 25 and'bit 16, and in addition, to effect removal of the materialbeing mined from the sleeve head 30. The sleeve head 30 with itsprotuberances 42 extend outwardly from the outer block face to enablethe free discharge of the material being mined from the passages betweenthe circumferentially spaced protuberances 42.

In the embodiment of FIGS. 1-3, the protuberances consist of fins on andextending substantially lengthwise of the sleeve head 30. These fins arepreferably inclined at an angle to the longitudinal axis of the sleeveand bit 16.

In the embodiment of FIG. 4, the protuberances 42- consist of individualknobs formed on and projecting laterally outwardly from the periphery ofthe sleeve head. These knobs can be randomly spaced, but it is preferredthat they be aligned in circumferentially spaced rows arranged at anangle to the longitudinal axis of the sleeve 25 and bit l6.

the mine face with a picking action to remove material from such face.The material being mined will move rearwardly over the sleeve head 30and into the passages between thecircumferentially spaced protuberances42, the material frictionally engaging the protuberances 42 and tendingto rotate the sleeve 25 in its mounting in theblock bore 11. Because thebit head 20 is forcefully urged against the sleeve head 30 during thispicking action, rotation of the sleeve 25 will cause a resultantrotationof the bit 16 carried within the sleeve 25. The bit 16 is movedto a'different angular position for each picking stroke. Consequently,all of the periphery of the tapered bit head 20 is presented to the wallin a picking action at different times in different angular positions,whereby the periphery of the tapered bit head 20. and carbide tip 24 isworn substantially evenly and .is maintained in a cutting, taperedconfiguration because it is self-sharpened.

It is thought that the usage and operation of the bit and block assemblyhave become apparent from the foregoing detailed description of parts,but for completeness of disclosure, it will be understood that the block10 is secured to a rotating head (not shown). The bit '16 is assembledto the sleeve 25 by inserting the bit shank 17 into the sleeve bore 34,and is locked in position by insertion of pin 40 into the sleeve shank26 and into the bit shank groove 41. The sleeve 25 is then assembled tothe block 10 by inserting the sleeve shank 26 into the block bore 11,and is locked in place by insertion of the pin 36 into the block 10 andinto the sleeve shank groove 37.

As the mining head (not shown) including the block 10 is rotated, thebit head 20 strikes the mine face at an angle so that the cutting tip 24penetrates the mine face and dislodges material with a picking action.The material moves rearwardly along the bit head 20 and over the sleevehead 30. More particularly, the material being mined moves into thepassages between the circumferentiallyspaced protuberances 42 andfrictionally engages such protuberances 42 to cause a turning of thesleeve 25 and hence of the bit 16 carried in the sleeve 25. The materialis discharged from the passages at the trailing end 32 of sleeve head 30laterally out wardly of the outer block face 15. Because the bit 16 isrotated during each picking stroke, the bit head 20 is self-sharpened bysubstantially even wear. This selfsharpening action of the bit head 20effectively increases the operating life of the bit 16.

I claim as my invention:

1. A bit and block assembly comprising:

a. a block movable along a mine face, the block being provided with asubstantially cylindrical bore,

b. a sleeve rotatively mounted in the block bore, the

sleeve being provided with a substantially cylindrical bore andincluding an enlarged head,

0. a point-attack bit for removing material from the mine faceincluding:

1. an elongate shank mounted in the sleeve bore,

2. an enlarged bit head integral and coaxial with the shank, the bithead having a leading end and a trailing end, and

3. a cutting tip on the leading end of the bit head penetrating thematerial being mined with a picking action upon travel of the bit alonga mine face, and d. a plurality of protuberances on and extendingoutwardly from the periphery of the sleeve head, the protuberancesextending generally longitudinally of and at an angle to thelongitudinal axis of the sleeve, the protuberances providing frictionalcontact with the material being mined to effect positive turning of thesleeve, and hence of the bit in the sleeve, upon picking of the mineface by the bit head. 2. A bit and block assembly as defined in claim 1,in which:

e. the protuberances consist of fins that are relativelycircumferentially spaced on the sleeve head. 3. A bit and block assemblyas defined in claim 1, in which:

e. the protuberances consist of individual knobs in circumferentiallyspaced rows on the sleeve head.

4. A bit and block assembly as defined in claim 1, in which:

e. the block has a front face and an adjacent outer face, the block boreextending through the block front face,

f. the sleeve head with its protuberances, engages the block front faceoutwardly of the block bore to position the sleeve in the block, and

g. the bit head engages the sleeve head to position the bit in thesleeve.

5. A bit and block assembly as defined in claim 1, in

which:

e. the protuberances are circumferentially spaced about the periphery ofthe sleeve head to provide longitudinal passages therebetween extendingfrom its leading end to its trailing end, the material being mined beingmovable through the passages and engageable with the protuberances,

f. the block has a front face and an adjacent outer face, the block boreextending through the block front face, and

g. the sleeve head with its protuberances engages the block front faceoutwardly of the block bore to position the sleeve in the block, andextends laterally outwardly beyond the outer block face vto enabledischarge of the material being mined from the passages between thecircumferentially spaced protuberances, and past the outer block face.

1. A bit and block assembly comprising: a. a block movable along a mineface, the block being provided with a substantially cylindrical bore, b.a sleeve rotatively mounted in the block bore, the sleeve being providedwith a substantially cylindrical bore and including an enlarged head, c.a point-attack bit for removing material from the mine faceincluding:
 1. an elongate shank mounted in the sleeve bore,
 2. anenlarged bit head integral and coaxial with the shank, the bit headhaving a leading end and a trailing end, and
 3. a cutting tip on theleading end of the bit head penetrating the material being mined with apicking action upon travel of the bit along a mine face, and d. aplurality of protuberances on and extending outwardly from the peripheryof the sleeve head, the protuberances extending generally longitudinallyof and at an angle to the longitudinal axis of the sleeve, theprotuberances providing frictional contact with the material being minedto effect positive turning of the sleeve, and hence of the bit in thesleeve, upon picking of the mine face by the bit head.
 2. an enlargedbit head integral and coaxial with the shank, the bit head having aleading end and a trailing end, and
 2. A bit and block assembly asdefined in claim 1, in which: e. the protuberances consist of fins thatare relatively circumferentially spaced on the sleeve head.
 3. a cuttingtip on the leading end of the bit head penetrating the material beingmined with a picking action upon travel of the bit along a mine face,and d. a plurality of protuberances on and extending outwardly from theperiphery of the sleeve head, the protuberances extending generallylongitudinally of and at an angle to the longitudinal axis of thesleeve, the protuberances providing frictional contact with the materialbeing mined to effect positive turning of the sleeve, and hence of thebit in the sleeve, upon picking of the mine face by the bit head.
 3. Abit and block assembly as defined in claim 1, in which: e. theprotuberances consist of individual knobs in circumferentially spacedrows on the sleeve head.
 4. A bit And block assembly as defined in claim1, in which: e. the block has a front face and an adjacent outer face,the block bore extending through the block front face, f. the sleevehead with its protuberances, engages the block front face outwardly ofthe block bore to position the sleeve in the block, and g. the bit headengages the sleeve head to position the bit in the sleeve.
 5. A bit andblock assembly as defined in claim 1, in which: e. the protuberances arecircumferentially spaced about the periphery of the sleeve head toprovide longitudinal passages therebetween extending from its leadingend to its trailing end, the material being mined being movable throughthe passages and engageable with the protuberances, f. the block has afront face and an adjacent outer face, the block bore extending throughthe block front face, and g. the sleeve head with its protuberancesengages the block front face outwardly of the block bore to position thesleeve in the block, and extends laterally outwardly beyond the outerblock face to enable discharge of the material being mined from thepassages between the circumferentially spaced protuberances, and pastthe outer block face.